// Copyright (c) 2010 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <stddef.h>

#include "base/logging.h"
#include "base/macros.h"
#include "base/strings/string_piece.h"
#include "base/strings/string_util.h"
#include "base/strings/utf_string_conversions.h"
#include "build/build_config.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace base {

namespace {

    const wchar_t* const kConvertRoundtripCases[] = {
        L"Google Video",
        // "网页 图片 资讯更多 »"
        L"\x7f51\x9875\x0020\x56fe\x7247\x0020\x8d44\x8baf\x66f4\x591a\x0020\x00bb",
        //  "Παγκόσμιος Ιστός"
        L"\x03a0\x03b1\x03b3\x03ba\x03cc\x03c3\x03bc\x03b9"
        L"\x03bf\x03c2\x0020\x0399\x03c3\x03c4\x03cc\x03c2",
        // "Поиск страниц на русском"
        L"\x041f\x043e\x0438\x0441\x043a\x0020\x0441\x0442"
        L"\x0440\x0430\x043d\x0438\x0446\x0020\x043d\x0430"
        L"\x0020\x0440\x0443\x0441\x0441\x043a\x043e\x043c",
        // "전체서비스"
        L"\xc804\xccb4\xc11c\xbe44\xc2a4",

    // Test characters that take more than 16 bits. This will depend on whether
    // wchar_t is 16 or 32 bits.
#if defined(WCHAR_T_IS_UTF16)
        L"\xd800\xdf00",
        // ?????  (Mathematical Alphanumeric Symbols (U+011d40 - U+011d44 : A,B,C,D,E)
        L"\xd807\xdd40\xd807\xdd41\xd807\xdd42\xd807\xdd43\xd807\xdd44",
#elif defined(WCHAR_T_IS_UTF32)
        L"\x10300",
        // ?????  (Mathematical Alphanumeric Symbols (U+011d40 - U+011d44 : A,B,C,D,E)
        L"\x11d40\x11d41\x11d42\x11d43\x11d44",
#endif
    };

} // namespace

TEST(UTFStringConversionsTest, ConvertUTF8AndWide)
{
    // we round-trip all the wide strings through UTF-8 to make sure everything
    // agrees on the conversion. This uses the stream operators to test them
    // simultaneously.
    for (size_t i = 0; i < arraysize(kConvertRoundtripCases); ++i) {
        std::ostringstream utf8;
        utf8 << WideToUTF8(kConvertRoundtripCases[i]);
        std::wostringstream wide;
        wide << UTF8ToWide(utf8.str());

        EXPECT_EQ(kConvertRoundtripCases[i], wide.str());
    }
}

TEST(UTFStringConversionsTest, ConvertUTF8AndWideEmptyString)
{
    // An empty std::wstring should be converted to an empty std::string,
    // and vice versa.
    std::wstring wempty;
    std::string empty;
    EXPECT_EQ(empty, WideToUTF8(wempty));
    EXPECT_EQ(wempty, UTF8ToWide(empty));
}

TEST(UTFStringConversionsTest, ConvertUTF8ToWide)
{
    struct UTF8ToWideCase {
        const char* utf8;
        const wchar_t* wide;
        bool success;
    } convert_cases[] = {
        // Regular UTF-8 input.
        { "\xe4\xbd\xa0\xe5\xa5\xbd", L"\x4f60\x597d", true },
        // Non-character is passed through.
        { "\xef\xbf\xbfHello", L"\xffffHello", true },
        // Truncated UTF-8 sequence.
        { "\xe4\xa0\xe5\xa5\xbd", L"\xfffd\x597d", false },
        // Truncated off the end.
        { "\xe5\xa5\xbd\xe4\xa0", L"\x597d\xfffd", false },
        // Non-shortest-form UTF-8.
        { "\xf0\x84\xbd\xa0\xe5\xa5\xbd", L"\xfffd\x597d", false },
        // This UTF-8 character decodes to a UTF-16 surrogate, which is illegal.
        { "\xed\xb0\x80", L"\xfffd", false },
    // Non-BMP characters. The second is a non-character regarded as valid.
    // The result will either be in UTF-16 or UTF-32.
#if defined(WCHAR_T_IS_UTF16)
        { "A\xF0\x90\x8C\x80z", L"A\xd800\xdf00z", true },
        { "A\xF4\x8F\xBF\xBEz", L"A\xdbff\xdffez", true },
#elif defined(WCHAR_T_IS_UTF32)
        { "A\xF0\x90\x8C\x80z", L"A\x10300z", true },
        { "A\xF4\x8F\xBF\xBEz", L"A\x10fffez", true },
#endif
    };

    for (size_t i = 0; i < arraysize(convert_cases); i++) {
        std::wstring converted;
        EXPECT_EQ(convert_cases[i].success,
            UTF8ToWide(convert_cases[i].utf8,
                strlen(convert_cases[i].utf8),
                &converted));
        std::wstring expected(convert_cases[i].wide);
        EXPECT_EQ(expected, converted);
    }

    // Manually test an embedded NULL.
    std::wstring converted;
    EXPECT_TRUE(UTF8ToWide("\00Z\t", 3, &converted));
    ASSERT_EQ(3U, converted.length());
    EXPECT_EQ(static_cast<wchar_t>(0), converted[0]);
    EXPECT_EQ('Z', converted[1]);
    EXPECT_EQ('\t', converted[2]);

    // Make sure that conversion replaces, not appends.
    EXPECT_TRUE(UTF8ToWide("B", 1, &converted));
    ASSERT_EQ(1U, converted.length());
    EXPECT_EQ('B', converted[0]);
}

#if defined(WCHAR_T_IS_UTF16)
// This test is only valid when wchar_t == UTF-16.
TEST(UTFStringConversionsTest, ConvertUTF16ToUTF8)
{
    struct WideToUTF8Case {
        const wchar_t* utf16;
        const char* utf8;
        bool success;
    } convert_cases[] = {
        // Regular UTF-16 input.
        { L"\x4f60\x597d", "\xe4\xbd\xa0\xe5\xa5\xbd", true },
        // Test a non-BMP character.
        { L"\xd800\xdf00", "\xF0\x90\x8C\x80", true },
        // Non-characters are passed through.
        { L"\xffffHello", "\xEF\xBF\xBFHello", true },
        { L"\xdbff\xdffeHello", "\xF4\x8F\xBF\xBEHello", true },
        // The first character is a truncated UTF-16 character.
        { L"\xd800\x597d", "\xef\xbf\xbd\xe5\xa5\xbd", false },
        // Truncated at the end.
        { L"\x597d\xd800", "\xe5\xa5\xbd\xef\xbf\xbd", false },
    };

    for (const auto& test : convert_cases) {
        std::string converted;
        EXPECT_EQ(test.success,
            WideToUTF8(test.utf16, wcslen(test.utf16), &converted));
        std::string expected(test.utf8);
        EXPECT_EQ(expected, converted);
    }
}

#elif defined(WCHAR_T_IS_UTF32)
// This test is only valid when wchar_t == UTF-32.
TEST(UTFStringConversionsTest, ConvertUTF32ToUTF8)
{
    struct WideToUTF8Case {
        const wchar_t* utf32;
        const char* utf8;
        bool success;
    } convert_cases[] = {
        // Regular 16-bit input.
        { L"\x4f60\x597d", "\xe4\xbd\xa0\xe5\xa5\xbd", true },
        // Test a non-BMP character.
        { L"A\x10300z", "A\xF0\x90\x8C\x80z", true },
        // Non-characters are passed through.
        { L"\xffffHello", "\xEF\xBF\xBFHello", true },
        { L"\x10fffeHello", "\xF4\x8F\xBF\xBEHello", true },
        // Invalid Unicode code points.
        { L"\xfffffffHello", "\xEF\xBF\xBDHello", false },
        // The first character is a truncated UTF-16 character.
        { L"\xd800\x597d", "\xef\xbf\xbd\xe5\xa5\xbd", false },
        { L"\xdc01Hello", "\xef\xbf\xbdHello", false },
    };

    for (const auto& test : convert_cases) {
        std::string converted;
        EXPECT_EQ(test.success,
            WideToUTF8(test.utf32, wcslen(test.utf32), &converted));
        std::string expected(test.utf8);
        EXPECT_EQ(expected, converted);
    }
}
#endif // defined(WCHAR_T_IS_UTF32)

TEST(UTFStringConversionsTest, ConvertMultiString)
{
    static char16 multi16[] = {
        'f', 'o', 'o', '\0',
        'b', 'a', 'r', '\0',
        'b', 'a', 'z', '\0',
        '\0'
    };
    static char multi[] = {
        'f', 'o', 'o', '\0',
        'b', 'a', 'r', '\0',
        'b', 'a', 'z', '\0',
        '\0'
    };
    string16 multistring16;
    memcpy(WriteInto(&multistring16, arraysize(multi16)), multi16,
        sizeof(multi16));
    EXPECT_EQ(arraysize(multi16) - 1, multistring16.length());
    std::string expected;
    memcpy(WriteInto(&expected, arraysize(multi)), multi, sizeof(multi));
    EXPECT_EQ(arraysize(multi) - 1, expected.length());
    const std::string& converted = UTF16ToUTF8(multistring16);
    EXPECT_EQ(arraysize(multi) - 1, converted.length());
    EXPECT_EQ(expected, converted);
}

} // namespace base
